Numerous ankle joint replacement prostheses have been developed.
U.S. Patent Application Publication No. 2014/0135939, assigned to the assignee of the present patent application, discloses an ankle prosthesis comprising: a tibial component configured for attachment to a tibia, and a talar component configured for attachment to a talus. The tibial component comprises an attachment surface on a proximal portion and an articulation surface on a distal portion. The talar component comprises an attachment surface on a distal portion and an articulation surface on a proximal portion. The articulation surface of the tibial component comprises at least one convex contour on a medial portion and at least one convex contour on a lateral portion. The articulation surface of the talar component comprises at least one concave contour on a medial portion and at least one concave contour on a lateral portion, configured to compliment the articulation surface of the tibial component. The articulation surface of the talar component comprises a lip configured to maintain congruence of the articulation surface of the tibial component with the articulation surface of the talar component.
The talar component is attached to the talus by one or more screws or one or more rods.